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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Sat, 09 Jul 2016 12:46:51 +1000
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Subject: Re: [Qemu-devel] [Qemu-ppc] [PULL 05/23] ppc: Enforce setting
 MSR:EE, IR and DR when MSR:PR is set
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To: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>, David Gibson <david@gibson.dropbear.id.au>, peter.maydell@linaro.org
Cc: qemu-devel@nongnu.org, qemu-ppc@nongnu.org, =?ISO-8859-1?Q?C=E9dric?= Le Goater <clg@kaod.org>

On Sat, 2016-07-09 at 01:43 +0100, Mark Cave-Ayland wrote:
> On 01/07/16 07:41, David Gibson wrote:
> 
> > From: Benjamin Herrenschmidt 
> > 
> > The architecture specifies that any instruction that sets MSR:PR will also
> > set MSR:EE, IR and DR.

 .../...

> Unfortunately this patch causes a regression and breaks booting OS 9 and
> OS X under qemu-system-ppc.

Any idea what is breaking specifically ? The architecture is pretty clear
here, could it be that they rely on old implementations allowing the
incorrect combination ?

Maybe we can make the restriction 64-bit server only...

Cheers,
Ben.